Practice projectile assembly

ABSTRACT

There is disclosed a practice projectile assembly comprised of a body  mem, a windshield member formed of a frangible material mounted to the body member thereby forming a chamber, a signal powder disposed in a portion of the chamber proximate the windshield member, and a piston member disposed in the chamber whereby upon impact of the projectile assembly the piston assembly assists in fracturing the windshield member to effect dispersion of the signal powder.

GOVERNMENTAL INTEREST

The Government has rights in this invention pursuant to contract numberDAAK-10-80-C-0211 awarded by the Department of the Army.

BACKGROUND AND FIELD OF THE INVENTION

This invention relates to a projectile assembly, and more particularlyto a practice projectile assembly.

The use of practice munitions as a training aid has been and isnecessary to finely hone the skills of the user. With certain forms ofmunitions, e.g. a high explosive dual purpose (HEDP) projectile, it isdesirable to produce a visible signal at the point of impact to permitobservation by the user or gunner of the effectiveness of his aiming ofthe weapon during launch of such a projectile. In this connection, theuse of frangible components and marker dyes are components in such aprojectile has been common, however, the effectiveness of suchprojectiles has been of a questionable nature. For example, theprojectile may not necessarily fracture upon impact on all types ofsurfaces; the projectile may fracture during normal handling and launch;the projectile may not provide adequate visual response upon impact;etc.

OBJECTS OF THE INVENTION

An object of the present invention is to provide an improved practiceprojectile assembly.

Another object of the present invention is to provide an improvedpractice projectile assembly exhibiting improved safety handlingcapabilities prior to launch.

A further object of the present invention is to provide an improvedpractice projectile assembly of improved visual impact effectiveness onall types of surfaces.

Yet another object of the present invention is to provide an improvedpractice projectile assembly producing a more observable visual effectupon impact.

A still further object of the present invention is to provide animproved practice projectile assembly exhibiting ballisticcharacteristics similar to an HEDP projectile.

Still another object of the present invention is to provide an improvedpractice projectile assembly formed of inexpensive materials ofconstruction.

Yet another object of the present invention is to provide an improvedpractice projectile assembly which is readily assembled in a facilemanner.

SUMMARY OF THE INVENTION

These and other objects of the present invention are achieved by aprojectile assembly comprised of a body member, a windshield memberformed of a frangible material mounted to the body member therebyforming a chamber, a signal powder disposed in a portion of the chamberproximate the windshield member, and a piston member disposed in thechamber whereby upon impact of the projectile assembly the pistonassembly assists in fracturing the windshield member to effectdispersion of the signal powder.

BRIEF DESCRIPTION OF THE DRAWING

A better understanding of the present invention will become moreapparent from the following detailed description thereof especially whentaken with the accompanying drawing of an elevational view, partially insection, of the present invention mounted in a cartridge base.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawing there is illustrated a practice projectilecartridge assembly, generally indicated as 10, and comprised of apractice projectile assembly, generally indicated as 12, mounted to acartridge case, generally indicated as 14. The practice projectileassembly 12 is comprised of a base member and a windshield member,generally indicated as 16 and 18, respectively, in which are disposed asignal powder and a piston member, generally indicated as 20 and 22,respectively.

The base member 16 is comprised of a body member 24 formed of acylindrically-shaped side wall portion 26 including anoutwardly-extending lip portion 28 formed about a terminal end thereof,and a hemispherically-shaped end wall portion 30 defining a cavity 32. Acylindrically-shaped band member 34 including ring-shaped riflingelements 36 is mounted about the cylindrically-shaped side wall portion26 of the body member 24. The body member 24 is formed, for example, byinjection molding techniques of a plastic material, such as phenyleneoxide reinforced with glass fibers, of sufficient structural strengthand exhibiting superior impact properties to withstand the impulse typeloads imposed by propellant gases. The band member 34 is formed of analuminum alloy to help spin the projectile and to maintain theprojectile's position with respect to the centerline of the barrel asthe projectile moves within the barrel. Generally, the band member 34 ismounted to the body member 24 in forming the base member 16 bypositioning the band member 34 in a body mold assembly prior toinjection molding of the body member 24. The band member 34 is fixed tothe body member 24.

The windshield member 18 is formed of a cylindrically-shaped side wallportion 38 and a dome-shaped end wall portion 40 defining a cavity 42.The side wall portion 38 of the windshield member 18 is formed with aplurality of radially and inwardly extending longitudinally disposed ribsections 44 (one shown) including a tapered surface 46 extendinginwardly towards the end wall portion 38 thereof. An interior surface ofthe side wall portion 38 of the windshield member 18 is formed with aninner groove 48 circumferentially-extending about the inner surface in aplane perpendicular to the axis of the windshield member 18 andcooperates with the lip portion 28 of the base member 16 as more fullyhereinafter described. The windshield member 18 is formed of a plasticmaterial, e.g. polystyrene exhibiting brittle physical properties toensure shattering of the windshield member 18 upon impact of theprojectile assembly 12. Generally, the plastic material should exhibitlow elongation.

In the cavity 42 of the windshield member 18 there is disposed thesignal powder 20 including a brightly colored dye component and otherparticulate material to provide suitable dispersion characteristics tothe signal powder 20 upon impact of the projectile member 12 to permitvisual observation thereof at far distances, e.g. 500 meters and more. Asuitable signal powder could be orange-yellow powder, or a fluorescentpigment forming a fine powder which disperses as an aerosol cloud uponfracturing of the windshield member 18 upon impact of the projectileassembly 12.

The piston member 22 is comprised of a hexagonally-shaped body section50 and an upper disc-shaped plate section 52 formed with a frustoconically-shaped outer surface 54 for cooperating with the taperedsurface 46 of the rib sections 44 of the windshield member 18 as morefully hereinafter described. The shape of the body section 50 of thepiston member 22, i.e. a hexagon, aids in the transmission of spin-uptorque thereto. The piston member 22 is formed of a material to achievea weight of the projectile assembly 12 proximate, and more preferablysubstantially identical to, that of an HEDP projectile, generally metal,e.g. steel. The piston member 22, in addition to providing ballast toachieve like weight characteristics, assists in the fracturing of thewindshield member 18 upon impact of the projectile assembly 12 at thetarget area. It will be understood by one skilled in the art that theprojectile assembly 12 of the present invention should be of an externalconfiguration substantially identical to an HEDP projectile and likewisepossess interior and exterior ballistic characteristics to such an HEDPprojectile.

Assembly of the practice projectile assembly 12 from its component partsis readily effected by initially placing the windshield member 18thereof in a holding fixture (not shown) with the end wall portion 40pointed in a downward position thereby permitting access to the cavity42. Into the cavity 42, there is disposed a suitable amount of thesignal powder 20 whereupon the plate section 52 of the piston member 22is inserted into the cavity 42 of the windshield member 18 to a pointwhere the outer surface 54 of the plate section 52 of the piston member22 contacts the tapered surface 46 of the rib sections 44 of thewindshield member 18. Thereupon, the base member 16 with the cavity 32thereof extending downwardly is inserted into the windshield member 18whereby outer and inner surface portions of the wall portions 26 and 38of the base member 16 and the windshield member 18, respectively, are incontacting relationship as illustrated in the drawing with downwardmovement of the base member 16 continued to a point where the lipportion 28 thereof is caused to be fully positioned within the groove 48formed in the interior surface of the side wall 38 of the windshieldmember 18, i.e. the base member 16 is snapped into position within thewindshield member 18. An adhesive, e.g. an epoxy resin, is applied aboutthe outer surface portion of the side wall 26 of the base member 16prior to positioning of the base member 16 within the windshield member18 to thereby fixedly position such member to each other.

As hereinabove discussed, the practice projectile cartridge assembly 10is comprised of the practice projectile assembly 12 mounted in thecartridge case 14. The cartridge case 14 is comprised of acylindrically-shaped base member 60 including an intermediate wallmember 62 having orifices 64 defining an upper U-shaped cavity 66 and alower cavity 68. In the lower cavity 68, there is disposed a propellant70 maintained by a base plug assembly 72. To form the cartridge assembly10, an adhesive or sealant 74 is applied about the inner surface portionof the cartridge base member 60 defining the upper cavity 66 and thepractice projectile assembly 12 inserted therein with the base member 16extending into the upper cavity 66 and an upper circularly-shaped edgeor lip portion 76 of the cartridge base 60 upset (not shown) into theband member 34 of the body member 16.

It will be appreciated by one skilled in the art that the presentinvention at the impact sight is chosen for one application to beexplosively inert and that no shrapnel is explosively generated therebyto minimize injury to personnel even in the impact area other than in aline of flight trajectory. Additionally, the absence of unexplodedprojectiles, e.g. duds, permits the use of the area for trainingexercises other than restricting use to explosive ranges. Further,minimal production costs may be realized since the plastic componentsmay be molded in a multiple-cavity mold by using conventional moldingequipment with metal parts being produced in automatic machines withminimal expenditure of labor.

In use, after launching from the cartridge case 14, and upon impact,inertial forces on the piston member 22 cause the piston member 22 tomove forward with the tapered surface 56 of the plate section 52 thereofto produce via the taperer surface 46 of rib sections 44 of thewindshield member 18 a lateral force thereon to cause the same to burstopen and release the signal powder 20. Such mechanical aid is quiteeffective and produces an almost 100% reliability on hard surfaces of atarget media, and about 80% reliability in rough target areas, i.e.areas consisting of vegetation and trees.

While the invention herein has been described in connection with anexemplary embodiment thereof, it will be understood that manymodifications will be apparent to those of ordinary skill in the art andthat this application is intended to cover any adaptations or variationsthereof.

What is claimed:
 1. A practice projectile assembly, which comprises:abase member; a windshield member formed of a frangible material anddefining a cavity; a signal powder disposed in said cavity of saidwindshield member; and a piston member positioned within a chamberformed by joining said base member and said windshield member, saidsignal powder being disposed between said piston member and saidwindshield member.
 2. The practice projectile assembly as defined inclaim 1 wherein said windshield member is formed of a brittle plasticmaterial.
 3. The practice projectile assembly as defined in claim 2wherein said windshield member is formed of a cylindrically-shaped sidewall having an inner surface and a dome-shaped end wall defining saidcavity, said inner surface of said side wall formed with a plurality ofrib sections having a surface tapered inwardly towards said end wall. 4.The practice projectile assembly as defined in claim 3 wherein saidpiston member is formed with a plate member having a frustoconically-shaped surface for cooperating with said tapered surface ofsaid rib sections of said windshield member.
 5. The practice projectileassembly as defined in claim 1 wherein said piston member is formed witha hexagonally-shaped body member axially disposed with respect to saidpractice projectile.
 6. The practice projectile assembly as defined inclaim 5 wherein said piston member is formed of a metal.
 7. The practiceprojectile assembly as defined in claim 1 wherein said base member isformed of a cylindrically-shaped side wall and a dome-shaped end wallthereby defining a cavity forming said chamber with said cavity of saidwindshield member.
 8. The practice projectile assembly as defined inclaim 7 wherein a band member is disposed about said side wall of saidbase member.
 9. The practice projectile assembly as defined in claim 8wherein said band member is formed with ring-shaped rifling elements.10. The practice projectile assembly as defined in claim 9 wherein saidband member is formed of a metal.
 11. The practice projectile assemblyas defined in claim 1 wherein said base member is formed of a plasticmaterial exhibiting good mechanical properties.
 12. A practice cartridgeassembly comprised of a practice projectile assembly as defined in claim1 mounted within a cartridge case assembly.